mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White to translucent
Luster: Vitreous to greasy

Identified March 23, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed from silica-rich hydrothermal fluids cooling in veins or from the crystallization of magma in igneous intrusions. Found in diverse geological environments ranging from Precambrian to Cenozoic.

Uses & applications

Used in the glass industry, as an abrasive, in decorative landscaping, and occasionally as a base material for ceramics. While low-value, it is a staple of beginner rock collections.

Geological facts

Milky quartz gets its cloudy white appearance from tiny microscopic inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz on Earth.

Field identification & locations

Identify in the field by its white color, lack of cleavage, and ability to scratch glass easily. It is ubiquitous worldwide, commonly found in mountain ranges, creek beds, and as large 'white veins' in darker host rocks.